Anchor for a well tool



Sept. 19, 1967 3 Sheets-Sheet 1 Original Filed Feb, 5, 1964 HENRY U. Gap/a577- INVENTOR. 1

Sept. 19, 1967 H. u. GARRETT ANCHOR FOR A WELL TOOL 3 Sheets-Sheet 2 Original Filed Feb. 5, 1964 INVENTOR.

BY A ISM! ATTOR/VEVJ P 1967 r H. u. GARRETT 3,342,269

ANCHOR FOR A WELL TOOL Original Filed Feb. 5, 1964 3 Sheets-Sheet 3 I /60 F/ 4 A 2/0 Z3 2/ NIL He/wy 4/ 642M977 INVENTOR.

LJWM/M ATTOR/VE VJ United States Patent 18 Claims. (c1. 166-137) ABSTRACT OF THE DISCLOSURE The invention provides an anchor particularly adapted for use with a well packer and involves a segmental expander coacting with gripping slips which are movable into gripping position with the well pipe. A mandrel on which the expander and slips are mounted has an enlargement or ring thereon and such ring coacts with the inner surfaces of the segments of the expander to either maintain the expander in its radially outward position or allow the expander to move radially inwardly; the mandrel is also utilized to exert a direct downward force on the resilient packer element when the anchor is combined with a packer and also provides a means which permits a force to be exerted on the slips in a direction maintaining the slips in gripping or set position. This abstract is neither intended to define the invention of the application which, of course, is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.

This application is a continuation of my earlier filed application, Ser. No. 342,622, filed Feb. 5, 1964 now abandoned.

This invention relates to an anchor for a well tool which will hold the tool against movement in one direction relative to the well pipe in which the tool is located. Anchors of the type to which this invention relates are commonly used in connection with well tools called packers which are located at various points in either the well casing or the well tubing to provide a seal for one reason or another. Usually a pressure differential will exist across the seal and thus an unbalanced force will be exerted on the packer tending to move it in one direction or the other relative to the well pipe in which it is located. Anchors are one means which can be used to prevent this movement and to hold the packers in position in sealing engagement with the well pipe.

To obtain the desired seal, packers are commonly provided with either cup-type or longitudinally compressable packing elements. The cup-type packing elements are designed to seal against pressure in one direction only and are pressure energized. Thus, these packing elements need only be located at the desired point in the well pipe and held against movement to provide the desired sealing function. I

The longitudinally compressable packing element, however, must be set, i.e. compressed longitudinally which forces it laterally into sealing engagement with the well pipe in which it is located. Thus in packers employing this type packing element the anchor must not only hold the packer against movement due to the differential pressure existing across it, but it must also hold the packing element in the set position.

The anchor of this invention can be used with either type packing element, however, it has particular utility in connection with packers which employ compression} type packing elements.

In these packers, the force for compressing the packing.

element can be provided in a number of ways If the packer is attached to another string of well pipe, the weight of the pipe can be used. The packer can also be set by various types of setting gun which are attached to the packer and located in the Well pipe by a wireline. Further, this type packer can be located and set on a wire line by using a jar-which will impart a series of hammer type blows on the packing element, each of which will partially compress the element. When setting a packer according to this latter method, by using wire line jars, since each incremental blow of the jars is insuflicient to completely set the packer, some means must be provided to hold in the packing element the amount of compression resulting from each blow. Otherwise, since the packing element is usually made of resilient material, the packing element would simply bounce back to its original size and shape after each blow of the jars. This holding or accumulating action has been obtained heretofore by ratcheting apparatus. However, this adds another mechanism to the packer which further complicates it and provides another possibility of a malfunction.

Thus, there is a need for an anchor for a well tool which will not only hold the tool against movement in one direction but which will hold in the packing element any compressive force placed therein, thus allowing the packing element to be set by a plurality of compressive blows, and it is an object of this invention to provide such an anchor.

It is a further object of this invention to provide an anchor for a well tool which also will hold any compressive force placed in the packing element from the direction opposite to that against which the anchor is resisting movement. Thus, should the packing element be further compressed, after it has been initially set, by the differential pressure which exists across it, then this anchor will hold this additional compression in the packing element, thereby reducing the possibility of the packer working loose and starting to leak due to a reversal of pressure differentials. It is another object of this invention to provide an anchor for a packer which transmits the force employed to set the packer, directly to the packing element, and not through the holding means on the anchor used to engage the well pipe and hold the packer against movement in one direction.

Anchors, of the type to which this invention is related, employ a slip and cone arrangement to hold the packing element against movement in one direction. The slips are usually provided with teeth which are forced into the wall of the well pipe by the wedging action of the cone and thus the larger the force exerted on the packer, the larger the lateral force which wedges the slips outwardly into engagement with the well pipe.

, This is a very eflicient way to anchor a well tool, however, the more slips are forced to bite into the surface of the walls of the well pipe, the more difficult they are to disengage from the well pipe, when the time comes to release the anchor and move the well tool in the well pipe. Heretofore, the slips were usually released by moving the cone longitudinally relative to the slips and by exerting a more or less longitudinal force on the slips. However, since the slips are forced into engagement with the well pipe by a lateral component of the downward force as a result of the tapered cone on which they are located, a lateral force in the opposite direction should be more effective in disengaging them from the well pipe.

Therefore, it is another object of this invention to 1 provide an anchor for a well tool, such as a well packer,

which when released will exert a lateral force on the slips of the anchor in the opposite direction to the force exerted on the slips when-the slips are forced outwardly into engagement with the walls of the well pipe to set the anchor.

In the design of anchors, the angle of the surface in the expander, which acts as the inclined plane for the slips, must be carefully considered. The flatter, i.e., the smaller the angle the surface makes with the longitudinal axis of the tool, the larger will be the lateral component ex erted on the slips for a given setting force. However, the flatter the angle, the harder the anchor will be to release. Therefore, the angle of the expander cone is usually a compromise.

It is another object of this invention to provide an anchor for a well tool wherein the slip expander provides a surface inclined at one angle for moving the slips out wardly into engagement with the well pipe but which provide another angle for releasing the slips.

It is another object of this invention to provide an expander cone which moves laterally outward when the slips are being moved into engagement with the pipe thereby reducing the distance the slips must travel along the inclined surface of the expander.

It is another object of this invention to provide an anchor for a well tool wherein the slips are resiliently urged laterally out of engagement with the well pipe when the tool is released.

These and other objects, advantages and features are obtained in accordance with this invention by providing an anchor which is attached to the well tool and slidably mounted on a mandrel which in turn connects the anchor to the running tool. By having the mandrel slidably mounted it can move into direct engagement with the well tool and transmit the force of the setting tool directly. Then by providing resilient means, which are actuated by the mandrel, to continuously urge the slip means of the anchor into engagement with the well pipe, the anchor will be in position to hold the well tool against movement opposite to that of the setting force, whenever the force is released.

In accordance with another aspect of the invention, the anchor is provided with a novel slip expander. It has the conventional frusto-conical surface for expanding the slips, however, as opposed to the slip expanding cones heretofore used in anchors of this type, the slip expanding cone of this invention is provided with a plurality of longitudinally extending slots which divides the cone into longitudinally extending fingers. Then by making the expander out of a resilient material, such as a spring steel, and attaching the slips to the fingers so that the movement of the fingers will be reflected in the slips, the fingers can be forced outwardly toward the wall of the well pipe when the tool is being set to flatten the angle of the surface moving the slips outwardly and to stress the fingers so that when it is desired to release the anchor the fingers can be released, and they will inherently tend to move inwardly due to their own resiliency and consequently exert a lateral force on the slips tending to pull the slips out of engagement with the wall of the well pipe.

One embodiment of the invention will now be described in detail in connection with the attached drawings in which,

FIGS. 1A, 1B and 1C illustrate an embodiment of the anchor of this invention employed with a packer having two longitudinally compressable packing elements which are used to bridge and seal off portions of well pipe, the figures showing the packer and anchor partially in elevation and partially in vertical section, as it appears when its packing elements are compressed and in sealing engagement with the well pipe and the anchor is in position holding the packing elements against movement in one direction relative to the well pipe;

FIG. 2 is a partial elevation and a partial vertical sectional view through the embodiment of the anchor and a portion of the packer of FIG. 1, showing the anchor as it appears preparatory to being run into the well pipe;

FIG. 3 is a cross-sectional view taken along line 33 of FIG. 2 illustrating how the slips in this embodiment of the anchor are attached to the resilient fingers of the slip expander;

FIG. 4 is a vertical sectional view of the expander of this embodiment; and

FIG. 5 is a view illustrating the anchor of FIG. 2 as it would appear after the anchor has been released from the well pipe allowing the tool to be removed therefrom.

The invention is shown in the drawings in connection with a bridging packer, however, it should be understood that this anchor could also be employed with many other types of packers or well tools wherein it is desired to hold the packer or tool against movement in one direction.

As illustrated in FIGS. 1A, 1B and 1C the bridging packer assembly generally illustrated by the number 10, is adapted to be run inside a well pipe 11. The packer assembly'10 includes an upper anchor section, generally indicated by the number 12, an upper packing element assembly, indicated generally by the number 13, a lower packing element assembly, indicated by the number \14, and a lower anchor assembly indicated by the number 15.

The embodiment of anchor 12 shown in FIG. 1A and FIG. 2, comprises mandrel 16, which is threadedly connected at its upper end to running sub 17 which is of a well known type used to run packers of this type on a wire line.

Encircling the lower portion of mandrel 16 is slip ex pander member 18. It has a cylindrical lower section 18a (FIG. 4), which is threadedly connected to upper packer section 13. Upper section 18b of this member is provided with a frusto-conical surface 180 and a plurality of longitudinally extending slots 19 which divide the upper end into a plurality of upwardly extending fingers 20. In the embodiment illustrated, four slots are provided to thereby divide the upper end of the member into four fingers.

Frusto-conical surface 18c on the upper end of these fingers provides inclined planes for moving slips 21 laterally outward as the slips are moved longitudinally downwardly relative to the fingers. Each finger is provided with a dove-tailed groove 22 (FIG. 3) to receive a slip 21 and slidably attach the slip to the finger. Preferably the slips are shaped with outwardly converging sides to match the outwardly converging sides of dove-tailed grooves 22 so that once the slips are placed within the grooves they can slide along the groove and thus be moved inwardly and outwardly laterally relative to the well pipe, however, they cannot move laterally relative to the groove. In this way any lateral movement of fingers 20 will also move slips 21 an equal amount.

Means are provided to bend fingers 20 outwardly as the slips are being set. Thus in the embodiment illustrated there is located on the inner surface of each finger 20 adjacent its outer end a protrusion 23, which when the tool is being run in the hole preparatory to being set, is located adjacent an annular ring 24, integrally attached to mandrel 16. Annular ring 24 is provided with an inclined surface 240 adjacent the end of protrusion 23 so that this surface can act as a cam to force the fingers outwardly when the mandrel moves downwardly relative to the fingers.

The upper edge 24b of annular ring 24, however, is under cut to engage the beveled surface 21b on slip heel 21a. Thus, surface 24b on the annular ring can engage surfaces 21b on the slips and hold the slips against lateral movement while the tool is being run in the hole.

Holding the surfaces 21b and 24b in engagement is coil spring 25 which is compressed between annular ring 26 and the lower end of running sub 17. Ring 26 transmits the force of coil spring 25 to the lower end of slips 21 to not only hold them in engagement with shoulder 24b, but to also urge them downwardly relative to the finger 20 when the anchor is being set. Therefore, the inner diameter of ring 26 is sufiicient to allow it to pass over annular ring 24.

While the tool is being run in the hole it is desirable that these members all maintain their relative positions as shown in FIG. 2, therefore, shear pin 27 extends through mandrel 16 and expander cone member 18 to prevent any relative movement between the mandrel and the expander member.

Packer assemblies 13 and 14 are identical and only one will be described in detail. Packer assembly 13 comprises two packing elements 28a and 28b which are made from an elastomeric material usually an oil resistant rubber, which are located so that they will be compressed longitudinally between two telescoping members to cause the elements to expand laterally into sealing engagement with the well pipe. The telescoping members comprise inner cylindrical member 29 and outer cylindrical mem- :ber 31. Member 29 is threadedly connected to slip expander member 18 through connector 30.

The longitudinal travel of member 31 relative to tubular member 29 in the downward direction is limited by interen gaging shoulders through which the weight of the lower packing assembly is transmitted through the tubular mem bers 31 and 29 and then to the running in string connected to sub 17 through anchor 12, during the time the tool is being lowered into the hole. A snap ring 32 is located in opposite annular grooves in members 2? and 31 to resist any inadvertent upward movement of member 31 relative to member 29 to thereby avoid any premature expanding of the packing elements while the tool is being run in the hole. This retaining ring for the lower packer need only resist inadvertent upward forces which may be encountered, however, the upper retaining ring should preferably be designed to allow the lower packer to be substantially completely set before it allows any of the setting force to be applied to the upper packer.

In between the two packing sections is a bridging member 33 of any desired length which separates the two packing sections so that they can be located on either side of the opening in the well pipe to be bridged.

Attached to the lower end of the tool is a conventional collar stop. It consists of a collet 34 having a plurality of resilient arms 35 which extend below a mandrel 36 and which are held inwardly out of engagement with the well pipe by a retaining ring 37. Attached to the retaining ring and extending below the well tool are a plurality of feelers 38 which have ends formed as hooks 39 which will move freely down the well pipe but which will engage the lower end of a section of pipe at the first joint it encounters when the well tool is moved upwardly.

When these feelers engage the lower end of a pipe section, they will move retaining ring 37 from shoulder 35a, on arms 35, to groove 35b. This allows resilient arms 35 to move outwardly far enough to allow shoulder 350 to engage the upper end of a pipe section at the joint, as shown in FIG. 1C. When this occurs, further downward travel of the well pipe will shear pin 42 allowing mandrel 36 to move down to wedge the resilient arms outwardly into secure engagement with the upper end of the section of well pipe, and positively hold the arms against inward movement. Thus, this collar stop allows the tool to be lowered into the well pipe to the desired point, then by raising of the well tool, the collar stop canbe actuated and caused to engage the pipe at a joint andresist any further downward movement of the tool.

In operation then, the well tool with the anchor in the position illustrated in FIG. 2 is lowered in the well pipe until it reaches the desired position where collar stop is actuated and further downward travel of the well tool is prevented. At this point sufficient weight is transmitted downwardly on upper running sub 17 to expand the packing elements 28a and 28b of both packing sections outwardly into sealing engagement with the well pipe and concomitantly therewith shear pin 27 allowing mandrel 16 to move downward relative to slip expander member 18.

Downward movement of the mandrel causes annular ring 24 to move under protrusions 23 and bend resilient fingers outwardly toward the well pipe. The outward movement of arms 20 also forces slips 21 outwardly toward the well pipe which retards their downward travel sufficiently to allow the undercut surface 24b of annular ring 24 to move out of engagement with beveled surface 21b on the slips, freeing them for movement along the inclined surfaces of fingers 20. Spring 25, of course, urges slips 21 downwardly along the inclined surfaces of the fingers which, in turn, forces them outwardly into engagement with the well pipe.

When sufficient compressive force has been placed in the packing elements to obtain the desired seal and this force is removed, slips 21 will be in position to be forced to bite into well casing 9 by the inclined surfaces on fingers 20 and prevent movement of expander cone 18 in an upward direction. By holding expander cone 18, of course, all of the portions of the packer therebelow will be held against upward movement relative to the well pipe and the compressive force placed in the packing elements will be maintained. As differential pressure is exerted across the packing elements in an upward direction, this will also be resisted by slips 21 in engagement with the well pipe.

When the time comes to remove the packing from the well pipe, anchor 12 must be released. This is accomplished by lifting up on running sub 17 which moves mandrel 16 upward relative to slip expander 18 until openings 16a move under protrusions 23. This allows fingers 20 to move inwardly due to their own resiliency which, in turn, will pull slips 21 out of engagement with the walls of the well pipe, freeing the tool for easy removal from the well.

The amount of spring force obtained by the outward bending of fingers 20 will depend upon the material out of which the fingers are made and the distance the fingers are bent. In the preferred form of the invention, member 18 is machined so that the diametrical distance between protrusions 23 is less than the outside diameter of mandrel 16 so that in the initial assembly of the anchor, the fingers will be forced outwardly thereby placing an initial stress in the fingers. Then when the fingers are moved further outwardly by the action of the expanding means during the setting of the anchor, an additional amount of stress will be placed in the fingers. In this way the total amount of force the fingers can exert on the slips to pull them out of engagement with the well pipe is increased.

Once the slips are free of the well pipe, the mandrel can be moved upwardly until the internal shoulder 40 of expander member 18 engages the opposing shoulder 41 on the mandrel and thus the entire weight of the packer assembly and anchor is once again supported by the running-in string attached to running sub 17 and the entire assembly can be removed from the well. If for some reason the fingers have not moved in when shoulder 41 engages shoulder 40, an additional inward force is exerted on the fingers by providing these interengaging shoulders with tapered surfaces as shown. 3

From the foregoing it will be seen that this invention is one well adapted to attain allof the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be'employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illus-' trative and not in a limiting sense.

i What I claim is:

1. In a packer,-for use in a well pipe, having a packing element and two members engaging the packing element with at least one member movable toward the other to move the packing element into sealing engagement with the well pipe, the improvement in combination therewith of an anchor for engaging the well pipe and holding the movable member against movement away from the other member while allowing the member to move toward the other member and force the packing element into sealing engagement with the well pipe, comprising, a slip expander member connected to the movable member and having a tapered outer surface adjacent the end away from the packing element; said slip expander being mounted for radial movement; slip means engaging the tapered surface on the slip expander member; a mandrel slidably mounted within the slip expander member for movement into engagement with the movable member to exert a force on the member and move the packing element into sealing engagement with the well pipe; an annular enlargement on said mandrel engageable with the inner surface of the slip expander member as the mandrel is moved into engagement with said movable member to exert a force on the latter, said enlargement coacting with the expander to maintain the slip expander member in its outermost radial position; and resilient means carried by the mandrel engaging the slip means for moving the slip means along the tapered surface on the slip expander into engagement with the well pipe and to move the slips with the slip expander as it moves toward the packing element as the packing element is compressed to hold the slip expander and the member against movement away from the packing element.

2. An anchor for a well tool adapted to engage the Walls of a well pipe and releasably hold a well tool against movement in one direction relative to the well pipe, comprising a mandrel; a slip expander of resilient material adapted to be attached to a well tool and slidably mounted on the mandrel to move longitudinally relative to the mandrel, said expander having one end portion provided with a frusto-conical outer surface and a plurality of longitudinally extending slots to divide said end portion into a plurality of resilient fingers having tapered outer surfaces adjacent their ends; a plurality of slip members slidably attached to the fingers; means for bending the fingers outwardly toward the wall of the well pipe when the anchor is at the desired location, and means for exerting a force on the slip members urging them longitudinally along the tapered surface of the fingers to cause them to move outwardly into engagement with the well pipe to wedge between the tapered surfaces on the fingers and the well pipe and hold the slip expander and the well tool against relative movement in one direction.

3. The anchor of claim 2 in which the resilient fingers of the slip expander are initially bent outwardly by the mandrel when the anchor is assembled.

4. The anchor of claim 3 in which the mandrel is provided with a plurality of openings arranged to be positioned under the fingers when the anchor is being released to allow the fingers to move inwardly and exert a lateral force on the slips urging them out of engagement with the well pipe.

5. The anchor of claim 2 in which the means for moving the fingers outwardly includes an annular ring externally mounted on the mandrel and arranged to move under the outer ends of the fingers and bend them outwardly when the anchor is being set.

6. The anchor of claim 5 in which the annular ring is located with one end adjacent the ends of the fingers and the opposite end in engagement with the slips, said interengaging surfaces in the slips and the ring being beveled and undercut respectively to allow the ring to hold the slips against laterally outward movement.

7. The anchor of claim 6 in which the means for exerting a force on the slip members urging them longitudinally along the tapered surface of the fingers comprises a coil spring.

8. An anchor for a well tool adapted to engage the walls of a well pipe and releasably hold a well tool against movement in one direction relative to the well pipe, comprising, a mandrel; a slip expander, adapted to be attached to a well tool, slidably mounted on the mandrel; said expander being made of a resilient material and having a plurality of longitudinally extending slots arranged to divide one end of the expander into a plurality of fingers, said fingers being provided with tapered surfaces adjacent their ends; a slip slidably attached to each finger for movement along the inclined surface; and disruptable means for holding the slip expander and the mandrel against relative longitudinal movement as the anchor is being positioned in a well pipe; releasable means for holding the slips against movement along the tapered surfaces on the finger in the direction which would cause them to move laterally outward; and means carried by the mandrel for engaging the fingers, when the disruptable holding means have been disrupted and the mandrel is moved relative to the slip expander, to bend the fingers outwardly.

9. The anchor of claim 8 in which the fingers are initially bent outwardly when the expander is assembled on the mandrel and the mandrel is provided with a plurality of openings positioned to be moved adjacent the fingers when the anchor is being released to allow the fingers to move inwardly into the openings.

10. An anchor for well tool adapted to engage the walls of a well pipe and releasably hold a well tool against movement in one direction relative to the well pipe, comprising, a mandrel; a slip expander, adapted to be attached to a well tool, slidably mounted on the mandrel; and having a plurality of longitudinally extending slots arranged to divide one end of the expander into a plurality of fingers, being arranged to be bent outwardly by themandrel when the expander is assembled on the mandrel; said fingers being further provided with tapered surfaces adjacent their ends; a slip slidably attached to each finger for movement along the inclined surface; disruptable means for holding the slip expander and the mandrel against relative longitudinal movement as the anchor is being positioned in a well pipe; an annular ring carried by the mandrel having one end undercut; an inclined surface being provided to engage the undercut surface on the ring and means for resiliently holding the two surfaces in engagement to thereby hold the slips against movement laterally outward and toward the fingers; said ring being located to move under the fingers when the disruptable means are disrupted to further bend the fingers outwardly and to release the slips to allow the resilient means to urge the slips along the inclined surface of the fingers when the anchor is being set; said mandrel being further provided with a plurality of openings located to be positioned under the fingers when the anchor is being released to allow the fingers to exert a force on the slips tending to move them laterally inward.

11. An anchor for a well tool adapted to engage the walls of a well pipe and releasably hold a well tool against movement relative to the well pipe comprising,

amandrel,

a slip expander adapted to be attached to a well tool and slidably mounted on the mandrel to move longitudinally relative to the mandrel,

said expander having one end portion formed with a frusto-conical outer surface,

said frusto-conical end portion being divided into arcuate segmental members having inner arcuate surfaces which members are movable inwardly and outwardly in radial directions,

a slip assembly including a plurality of gripping slips surrounding the mandrel above the expander and mounted for slidable movement with respect to the frusto-conical surface of the end portion of the expander, whereby the relative position of said slip assembly with respect to said surface controls the engagement and disengagement of the slips with the pipe wall,

an annular ring means secured to and forming part of the mandrel and adapted to coact with the inner arcuate surfaces of the segmental members to urge 9 the same radially outwardly upon movement of the mandrel relative to said members,

said coacting ring means being movable to a first position relative to the expander in which first position said means is not coacting with the inner surfaces of the segmental members and also being movable to a second position in which the said means coacts with said segmental members to move and maintain said members radially outward, and

means actuated by the movement of the mandrel relative to the slips for exerting a downward force upon the slips urging them longitudinally along the frustoconical surface formed by the segmental members of the end portion of the expander while said segmental members are maintained radially outwardly by said coacting ring means to thereby move said slips into gripping engagement with the well pipe.

12. The combination with a well packer for use in a well pipe and having packing element confined between upper and lower abutments which are movable toward each other to apply endwise force to the element to deform the same into sealing engagement with well pipe, of an anchor device comprising,

amandrel,

a slip expander slidably mounted on the mandrel and connected to one of the confining abutments of the packer,

a slip assembly including a plurality of slips surrounding the mandrel above the expander and mounted for slidable movement with respect to expander,

said slip expander having its upper end formed of a plurality of segments which are movable radially inwardly and outwardly with respect to the mandrel,

said segments having their upper portions shaped to form a substantially frusto-conical outer surface with which the slips coact upon relative movement between the slips and expander,

an annular ring secured to and forming part of the mandrel and located in a transverse plane which is outside the bore formed by the inner surfaces of the segments to allow movement of the segments to their inward radial positions,

movement of the mandrel relative to the expander moving said annular ring into the bore formed by said inner surfaces of said segments to urge and maintain said segments in their radially outward positions, and

means for applying a downward force to the slip assembly after the segments have been moved and are being maintained in their radially outward position by said annular ring to thereby move the slips of said assembly into gripping engagement with the pipe.

13. In a packer, for use in a well pipe, having a packing element and two members engaging the packing element with at least one member movable toward the other to move the packing element into sealing engagement with the well pipe, the improvement in combination therewith of an anchor for engaging the well pipe and holding the movable member against movement away from the other member while allowing the member to move toward the other ember and force the packing element into sealing engagement with the well pipe, comprising,

a slip expander member connected to the movable member and having a tapered outer surface adjacent the end away from the packing element,

slip means engaging the tapered surface on the slip expander member,

a mandrel slidably mounted within the slip expander member for movement into engagement with the movable member to exert a force on the member and move the packing element into sealing engagement with the well pipe,

resilient means carried by the mandrel engaging the slip means for moving the slip means along the tapered surface on the slip expander into engagement with the well pipe and to move the slips with the slip expander as it moves toward the packing element as the packing element is compressed to hold the slip expander and the member against movement away from the packing element,

said slip expander being made of resilient material and being provided with longitudinally extending slots to divide the end having the tapered outer surface into a plurality of fingers, and

expanding means carried by the mandrel for bending the fingers outwardly toward the well pipe when the packing element is being compressed.

14. The combination of claim 13 in which the slip means are slidably attached to the fingers to allow the fingers to exert an inward force on the slip means when the expanding means is moved out of engagement with the fingers.

15. An anchor for a well tool adapted to engage the walls of a well pipe and releasably hold a well tool against movement relative to the Well pipe comprising,

a mandrel,

a slip expander adapted to be attached to a well tool and slidably mounted on the mandrel to move longitudinally relative to the mandrel,

said expander having one end portion formed with a frusto-conical outer surface,

said frusto-conical end portion being divided into arcuate segmental members having inner arcuate surfaces which members are movable inwardly and outwardly in radial directions,

a slip assembly including a plurality of gripping slips surrounding the mandrel and mounted for slidable movement with respect to the frusto-conical surface of the end portion of the expander, whereby the relative position of said slip assembly with respect to said surface controls the engagement and disengagement of the slips with the pipe wall,

an annular ring means secured to the mandrel and adapted to coact with the inner arcuate surfaces of the segmental members to urge the same radially outwardly upon movement of the mandrel relative to said members,

said coacting ring means being movable to a first position relative to the expander in which first position said means is not coacting with the inner surfaces of the segmental members and also being movable to a second position in which the said means coacts with said segmental members to move and maintain said members radially outward,

means for exerting a force upon the slips urging them longitudinally along the frusto-conical surface formed by the segmental members of the end portion of the expander while said segmental members are maintained radially outwardly by said coacting ring means to thereby move said slips into gripping engagement with the well pipe, and

means releasably securing the mandrel against movement with respect to the expander to locate the coacting ring means in its first position relative to the expander to allow the anchor to be lowered to the desired position in the well pipe.

16. An anchor for a well tool adapted to engage the walls of a well pipe and releasably hold a well tool against movement relative to the well pipe comprising,

a mandrel,

a slip expander adapted to be attached to a well tool and slidably mounted on the mandrel to move longitudinally relative to the mandrel,

said expander having one end portion formed with a frusto-conical outer surface,

said frusto-conical end portion being divided into arcuate segmental members having inner arcuate surfaces which members are movable inwardly and outwardly in radial directions,

a slip assembly including a plurality of gripping slips surrounding the mandrel and mounted for slidable movement with respect to the frusto-conical surface of the end portion of the expander, whereby the relative position of said slip assembly with respect to said surface controls the engagement and disengagement of the slips with the pipe wall,

an annular ring means secured to the mandrel and adapted to coact with the inner arcuate surfaces of the segmental members to urge the same radially outwardly upon movement of the mandrel relative to said members,

' said coacting ring means being movable to a first position relative to the expander in which first position said means is not coacting with the inner surfaces of the segmental members and also being movable to a second position in which the said means coacts with said segmental members to move and maintain said members radially outward,

means for exerting a force upon the slips urging them longitudinally along the frusto-conical surface formed by the segmental members of the end portion of the expander while said segmental members are maintained radially outwardly by said coacting ring means to thereby move said slips into gripping engagement with the well pipe, and

an abutment on the expander, and

support means on the mandrel engageable with said abutment,

the position of said support means on the mandrel being such that a movement of the mandrel relative to the expander which is sufficient to move the coacting means out of engagement with the inner surfaces of the segmental members of the expander, causes said support means on the mandrel to engage said abutment within the expander whereby subsequent movement of the mandrel will remove the anchor from the well pipe.

17. The combination with a well packer for use in a well pipe and having a packing element con-fined between upper and lower abutments which are movable toward each other to apply endwise force to the element to deform the same into sealing engagement with well pipe, of an anchor device comprising,

a mandrel,

a slip expander slidably mounted on the mandrel and connected to one of the confining abutments of the packer,

a slip assembly including a plurality of slips surrounding the mandrel above the expander and mounted for slidable movement with respect to expander,

said slip expander having its upper end formed of a plurality of segments which are movable radially inwardly and outwardly with respect to the mandrel,

said segments having their upper portions shaped to form a substantially frusto-conical outer surface with which the slips coact upon relative movement between the slips and expander,

an annular ring secured to the mandrel and located in a transverse plane which is outside the bore formed by the inner surfaces of the segments to allow movement of the segments to their inward radial positions,

movement of the mandrel relative to the expander moving said annular ring into the bore formed by said inner surfaces of said segments to urge and maintain said segments in their radially outward positions,

means for applying a downward force to the slip assembly after the segments have been moved and are being maintained in their radially outward position by said annular ring to thereby move the slips of said assembly into gripping engagement with the pipe, and

means releasably securing the mandrel to the expander to locate the annular ring on said mandrel in its position outside the bore formed by the inner surfaces of the segments to allow the anchor to be lowered to the desired position in the well pipe.

18. The combination with a well packer for use in a well pipe and having a packing element confined between upper and lower abutments which are movable toward each other to apply endwise force to the element to deform the same into sealing engagement with well pipe, of an anchor device comprising,

a mandrel,

a slip expander slidably mounted on the mandrel and connected to one of the confining abutments of the packer,

a slip assembly including a plurality of slips surrounding the mandrel above the expander and mounted for slidable movement with respect to expander,

said slip expander having its upper end formed of a plurality of segments which are movable radially inwardly and outwardly respect to the mandrel,

- said segments having their upper portions shaped to form a substantially frusto-conical outer surface with which the slips coact upon relative movement between the slips and expander,

an annular ring secured to the mandrel and located in a transverse plane which is outside the bore formed by the inner surfaces of the segments to allow movement of the segments to their inward radial positions,

movement of the mandrel relative to the expander moving said annular ring into the bore formed by said inner surfaces of said segments to urge and maintain said segments in their radially outward positions,

means for applying a downward force to the slip assembly after the segments have been moved and are being maintained in their radially outward position by said annular ring to thereby move the slips and said assembly into gripping engagement with the pipe,

release of the anchor is effected by upward movement of the mandrel relative to the expander and slips, and

support means on the mandrel and engageable with at least one element of the anchor whereby removal of the mandrel from the well pipe simultaneously removes said anchor.

References Cited UNITED STATES PATENTS 802,880 10/1905 Phillips 166-137 892,776 7/1908 Tirk 166-137 2,173,351 9/1939 Bradshaw 166-140 2,274,940 3/ 1942 Stoddard 166-137 X 2,714,931 8/1955 Bouvier 166-135 X 2,751,017 6/ 1956 Baker et al 166-134 X 2,906,344 9/1959 Clark 166-140 2,944,604 7/1960 Baker 166-137 3,024,845 3/1962 Conrad 166-134 X CHARLES E. OCONNELL, Primary Examiner.

DAVID H. BROWN, Examiner. 

1. IN A PACKER, FOR USE IN WELL PIPE, HAVING A PACKING ELEMENT AND TWO MEMBERS ENGAGING THE PACKING ELEMENT WITH AT LEAST ONE MEMBER MOVABLE TOWARD THE OTHER TO MOVE THE PACKING ELEMENT INTO SEALING ENGAGEMENT WITH THE WELL PIPE, THE IMPROVEMENT IN COMBINATION THEREWITH OF AN ANCHOR FOR ENGAGING THE WELL PIPE AND HOLDING THE MOVABLE MEMBER AGAINST MOVEMENT AWAY FROM THE OTHER MEMBER WHILE ALLOWING THE MEMBER TO MOVE TOWARD THE OTHER MEMBER AND FORCE THE PACKING ELEMENT INTO SEALING ENGAGEMENT WITH THE WELL PIPE, COMPRISING, A SLIP EXPANDER MEMBER CONNECTED TO THE MOVABLE MEMBER AND HAVING A TAPERED OUTER SURFACE ADJACEN THE END AWAY FROM THE PACKING ELEMENT; AND SLIP EXPANDER BEING MOUNTED FOR RADIAL MOVEMENT; SLIP MEANS ENGAGING THE TAPERED SURFACE ON THE SLIP EXPANDER MEMBER; A MANDREL SLIDABLY MOUNTED WITHIN THE SLIP EXPANDER MEMBER FOR MOVEMENT INTO ENGAGEMENT WITH THE MOVABLE MEMBER TO EXERT A FORCE ON THE MEMBER AND MOVE THE PACKING ELEMENT INTO SEALING ENGAGEMENT WITH THE WELL PIPE; AN ANNULAR ENLARGEMENT ON SAID MANDREL ENGAGEABLE WITH THE INNER SURFACE OF THE SLIP EXPANDER MEMBER AS THE MANDREL IS MOVED INTO ENGAGEMENT WITH SAID MOVABLE MEMBER TO EXERT A FORCE ON THE LATTER, SAID ENLARGEMENT COACTING WITH THE EXPANDER TO MAINTAIN THE SLIP EXPANDER MEMBER IN ITS OUTERMOST RADIAL POSITION; AND RESILIENT MEANS CARRIED BY THE MANDREL ENGAGING THE SLIP MEANS FOR MOVING THE SLIP MEANS ALONG THE TAPERED SURFACE ON THE SLIP EXPANDER INTO ENGAGEMENT WITH THE WELL PIPE AND TO MOVE THE SLIPS WITH THE SLIP EXPANDER AS IT MOVES TOWARD THE PACKING ELEMENT AS THE PACKING ELEMENT IS COMPRESSED TO HOLD THE SLIP EXPANDER AND THE MEMBER AGAINST MOVEMENT AWAY FROM THE PACKING ELEMENT. 